Medication vial and bottle caps are widely used in the containment of tablets, capsules, powders, liquids and other medication forms. It is widely accepted that patients are poorly compliant in taking medication according to the recommended dosing schedule, and that such noncompliance can have serious consequences for the patient's health. Further, it is known that one large component of patient noncompliance is forgetting. Patients simply get too busy and fail to follow the medication schedule.
The idea of having a medication vial cap to remind patients to take their medication on schedule is well known. Basic to the reminder function is the requirement to monitor openings and closings of the vial as a means of inferring the patient's compliance with the prescribed regimen. This in turn requires a means of determining when the vial cap is removed. Such means are widely taught in the form of switches that determine when the cap is removed. Such switches are typically integrated into or applied to the cap.
Devices to determine bottle openings and closings are typically mechanical or electromechanical, and require means integrated in the cap to detect rotation of the cap relative to the vial. There are limitations to such devices in that they are complex, expensive to manufacture, and are not robust having limited number of open-close cycles due to their mechanical nature and moving parts.
A further limitation is that most such caps are limited to the containment of capsules, tablets and other compressed solid formats and cannot be used for powders or liquids. Vial and bottle caps generally comprise a screw-on component that houses an internal seal. Those designed to monitor patient compliance typically have two parts to the shell the upper of which contains the required electronics and is attached atop the lower component housing a snap-in clear plastic insert with screw threads for connecting to the vial and a sealing surface. Because of the requirement for a means of detecting the rotation of the cap relative to the vial and the interference of such means with the integrity of the cap's insert and/or sealing surface, such caps are not suitable for vials of liquids or powders due to the possibility of leakage.